This invention relates to direct current motors and more particularly to a motor having coils or magnets interposed between magnetizable members establishing a plurality of magnetic pole shoes for exciting an armature.
1. Field of the Invention
This application is distinctive over the first named copending application by disclosing a motor in which each pole piece of the respective pairs of pole pieces is physically divided to form dual pole shoes of each pair of pole shoes and is distinctive over both of the above copending applications by disclosing the division of the magnetic flux of the respective pole shoe in its longitudinal surface facing a peripheral portion of an armature.
Conventional direct current motors usually comprise a metallic housing journalling an armature with sectional field coils or stator windings contained by the housing which substantially surround the armature to provide a magnetic circuit for exciting the armature.
In this type of design one armature is operated by each group of stators or field windings resulting in inefficient utilization of the various circuits established, thus, limiting the potential of the magnetic circuit established by direct current through coils interposed between magnetizable pole pieces.
The relationship of magnetic material (iron) and magnetics is the most difficult problem to overcome in a DC motor, for the reason the metal forming the segments of the winding lobes of the rotor are naturally attracted by the magnetics of the field creating an unfavorable or counter electromotive force. The unfavorable force must be overcome as each segment of the rotor passes through the magnetic field. In order to overcome the unfavorable force, the motor must consume more energy or current.
Conventional technology can only use the major forces of magnetic attraction to cause a rotor to rotate within the magnetic field. The other remaining force, repulsion, cannot be utilized as a major force in a conventional DC motor.
The force of repulsion cannot advantageously be used because of its strategic location to the rotor.
This invention also changes the design of the correlation of the pole shoes relative to the armature. This invention allows the use of the repelling forces as well as the attracting forces to be utilized in the operation of a DC motor.
Normally generated magnetic current concentrates the strength of the polarity forces in the center of the magnetic pole core, e.g., a north pole of a magnet has the greatest strength at the center on the north pole. The same is true for the south pole. The flux patterns of normally generated magnetic current are eliptical. This invention changes the eliptical flux patterns to linear or straight. By this change in the flux patterns, the flux can be directed or concentrated to strategic locations on the armature.
Magnetic forces realigned within the field of the motor become absolute and operate at a consistently uniform pattern. Realignment of these forces capitalizes the maximum use or conversion of the energy into output torque and speed at the shaft of the motor.
This invention realigns these forces in a uniform plane by connecting carrier plates of soft iron to like poles of magnetic sources, either permanent or electromagnets, thereby allowing the forces to be utilized as a uniform pattern of magnetic flux regardless of their path as long as the air gap between the carrier plates is constant. This application of uniform magnetic flux allows several usable configurations, within the field, to be constructed to direct the flux to the rotor. With the addition of the uniform patterns of flux forces it is now possible to utilize the total effects of the two opposing forces, attraction and repulsion (force and counter force) of the same polarity, of both the field and the rotor, and eliminate the unfavorable force that would normally be present.
The creation of a uniform flux pattern within the field allows the use of additional areas of leverage to be applied to the rotor. To achieve these additional areas of leverage the carrier plate or pole shoe is divided. Two of the parts become dual pole shoes located precisely in relation to the winding of the rotor and a third part serves as a separation of the dual pole shoes. The separation or division of a single pole shoe operating in the same area of the armature field removes the potential of the unfavorable forces normally found in conventional DC motors. This application occurs at each of the opposing magnetically supplied field working forces. The addition of the points of leverage in a two pole motor will now become a four pole shoe two brush motor, and a four pole shoe four brush motor will become a four brush eight pole shoe motor. The addition of twice the leverage on the rotor by the field will increase the speed and the torque and only raise the current demand slightly.
2. Description of the Prior Art
The most pertinent patent is believed to be U.S. Pat. No. 5,212,418 issued to Mason on May 18, 1993 for HIGH TORQUE AND SPEED DC MOTORS.
This patent discloses some of the features of the motor of this invention, but does not disclose the diametrically opposite separate pairs of dual pole shoes having like polarity magnetic flux applied to respective ends of each pole shoe extending longitudinally of an armature for obtaining desired torque and speed or both of the armature and efficient use of input amperage as disclosed by this invention.